Hello Dean and Amelian friends
As I was planning to leave Ipanema on the hard, for one month I was offered a dehumidifier at the yard in Cartagena. In addition to the issue of collecting the condensing water into the bilge, It was clear that it added heat to that already generated caused by the two freezers and the refrigerator. This made the boat extremely hot since the dust and rust particles in the air required that the boat be left sealed from the environment.
My solution was to buy a small and inexpensive (<$100) window-mounted air conditioning unit and run it at a relatively high temperature (27 C). I did not have the time to mount it on a hatch but I realized that it could be easily slid onto the grooves of the companionway door using the hardware that came with the AC unit. To allow entry onto the boat I mounted it with the door fully opened and made a piece of plexiglass to cover the gap above it (see foto). I further added hardware that allowed me to lock the system with a small lock. Obviously, this is not to prevent forced entry onto the boat but to have the means to know if there was a forced entry to the boat in my absence that I could report to the Marina or the yard.
The AC unit extracts the humidity in addition to cooling the boat. The resulting water usually drips out from the back (external) of the unit but the one I found is actually sprayed by the fan on the condenser further contributing to the unit's high efficiency. and avoiding the drip of dirty water on the deck.
After a month in the tropics, I found the boat dry and cool at a minimal electrical cost.
After I moved to Panama I decided to leave the system running as an air conditioning unit at less than 1/2 the cost of using one of the water-cooled AC units on Ipanema and, very importantly, without using saltwater that can bring gelly fish and other creatures to the strainer.
To spread the cool around the boat I turned the AC unit flaps to starboard and kept the fan on the navigation table pointing towards the stern passage. The airflow onto the aft cabin was further enhanced by keeping the fan in the battery room ON and mounting a small fan on the port shelve to further direct the airflow back. The results have been soo good that I decided not to move the AC unit to the hatch and simply walk over it adding a small temporary plastic step to the companionway stair. The unit uses <500 wats at a cost of $4/day for running 24-7 at the marina. To simplify the opening and closing of the companionway I added one of the spare Amel screws to the top of the Plexiglas window/door